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Development of spatial suppression surrounding the focus of visual attention

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 نشر من قبل Audrey Wong-Kee-You MA
 تاريخ النشر 2018
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The capacity to filter out irrelevant information from our environment is critical to efficient processing. Yet, during development, when building a knowledge base of the world is occurring, the ability to selectively allocate attentional resources is limited (e.g., Amso & Scerif, 2015). In adulthood, research has demonstrated that surrounding the spatial location of attentional focus is a suppressive field, resulting from top-down attention promoting the processing of relevant stimuli and inhibiting surrounding distractors (e.g., Hopf et al., 2006). It is not fully known, however, whether this phenomenon manifests in development. In the current study, we examined whether spatial suppression surrounding the focus of visual attention is exhibited in developmental age groups. Participants between 12 and 27 years of age exhibited spatial suppression surrounding their focus of visual attention. Their accuracy increased as a function of the separation distance between a spatially cued (and attended) target and a second target, suggesting that a ring of suppression surrounded the attended target. When a central cue was instead presented and therefore attention was no longer spatially cued, surround suppression was not observed, indicating that our initial findings of suppression were indeed related to the focus of attention. Attentional surround suppression was not observed in 8- to 11-years-olds, even with a longer spatial cue presentation time, demonstrating that the lack of the effect at these ages is not due to slowed attentional feedback processes. Our findings demonstrate that top-down attentional processes are still immature until approximately 12 years of age, and that they continue to be refined throughout adolescence, converging well with previous research on attentional development.



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